A suction device is specified for surgeries or other medical treatments in order to make it possible to clear the throat by suction in case the patient vomits. Further, body fluids, which obstruct the view to the wound, are suctioned and collected in collecting containers. The collecting containers are disposed of after the surgery. The collecting containers must collect body fluids hygienically, i.e., the body fluids must not escape to the outside and also not into the pumping device.
It is known that full collecting containers may be replaced with empty collecting containers during the surgery. However, the suction of the body fluid is interrupted hereby. Even if collecting containers of different sizes are available, the quantity of body fluid that will be discharged and must then be collected must be estimated in advance. Should this estimate be incorrect, it will be necessary to change the collecting container despite the preparatory estimation. The surgeon cannot optimally see the wound any longer due to the interruption during the replacement of the collecting container and the time needed for the entire surgery may become longer, which is disadvantageous for the patient. If an excessively large collecting container was selected, the work process is inefficient, because a collecting container is not usually used for a plurality of surgeries for hygienic reasons.
Further, the time needed for evacuating the container, during which no wound secretion can be suctioned, will increase.
It is known in this connection that a plurality of collecting containers may be connected in series or parallel. The containers are equipped here with valves, which are opened via floats, which indicate the filling level in the collecting container being filled. This device, with the combination of the floats and valves, has a complicated configuration and is susceptible to malfunction, because, for example, a float may be stuck or an error may occur in the valve control and the corresponding valve will not consequently open or will not open in time.